refactror: Move osgi from flow

.gitignore

@@ -1 +1 @@
-/target/
+**/target/

flow-osgi/bnd.bnd

@@ -3,6 +3,5 @@ Bundle-Name: Vaadin Flow OSGi Support
 Bundle-Version: ${osgi.bundle.version}
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8
 Bundle-License: http://www.apache.org/licenses/LICENSE-2.0
-Import-Package: *
 Export-Package: com.vaadin.flow.osgi.support*
 

flow-osgi/pom.xml

@@ -40,7 +40,7 @@
 
         <dependency>
             <groupId>org.osgi</groupId>
-            <artifactId>org.osgi.core</artifactId>
+            <artifactId>osgi.core</artifactId>
             <version>${osgi.core.version}</version>
             <scope>provided</scope>
         </dependency>
@@ -51,6 +51,7 @@
             <version>${osgi.compendium.version}</version>
             <scope>provided</scope>
         </dependency>
+
         <dependency>
             <groupId>org.apache.httpcomponents</groupId>
             <artifactId>httpclient-osgi</artifactId>

flow-osgi/src/main/java/com/vaadin/flow/osgi/support/OSGiInstantiatorFactory.java

@@ -22,6 +22,8 @@
 import com.vaadin.flow.server.VaadinServiceInitListener;
 
 /**
+ * OSGi capable implementation of instantiator factory.
+ * 
  * @author Vaadin Ltd
  * @since
  *

flow-osgi/src/main/java/com/vaadin/flow/osgi/support/OSGiResourceProvider.java

@@ -0,0 +1,105 @@
+/**
+ * Copyright (C) 2020 Vaadin Ltd
+ *
+ * This program is available under Commercial Vaadin Developer License
+ * 4.0 (CVDLv4).
+ *
+ *
+ * For the full License, see <https://vaadin.com/license/cvdl-4.0>.
+ */
+package com.vaadin.flow.osgi.support;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.List;
+import java.util.Objects;
+
+import org.osgi.framework.Bundle;
+import org.osgi.framework.FrameworkUtil;
+import org.osgi.service.component.annotations.Component;
+
+import com.vaadin.flow.di.ResourceProvider;
+import com.vaadin.flow.server.VaadinServletService;
+
+/**
+ * OSGi capable implementation of {@link ResourceProvider}.
+ * ServiceComponentRuntime activates this Service because of @Component
+ * 
+ * @author Vaadin Ltd
+ * @since
+ *
+ */
+@Component
+public class OSGiResourceProvider implements ResourceProvider {
+
+    @Override
+    public URL getApplicationResource(Class<?> clazz, String path) {
+        return FrameworkUtil.getBundle(Objects.requireNonNull(clazz))
+                .getResource(path);
+    }
+
+    @Override
+    public URL getApplicationResource(Object context, String path) {
+        Class<?> appClass = getApplicationClass(context);
+        if (appClass == null) {
+            return null;
+        }
+        return getApplicationResource(appClass, path);
+    }
+
+    @Override
+    public List<URL> getApplicationResources(Object context, String path)
+            throws IOException {
+        Class<?> appClass = getApplicationClass(context);
+        if (appClass == null) {
+            return Collections.emptyList();
+        }
+        return getApplicationResources(appClass, path);
+
+    }
+
+    @Override
+    public List<URL> getApplicationResources(Class<?> clazz, String path)
+            throws IOException {
+        Bundle bundle = FrameworkUtil.getBundle(Objects.requireNonNull(clazz));
+        Enumeration<URL> resources = bundle.getResources(path);
+        if (resources == null) {
+            return Collections.emptyList();
+        }
+        return Collections.list(resources);
+    }
+
+    @Override
+    public URL getClientResource(String path) {
+        Bundle[] bundles = FrameworkUtil.getBundle(OSGiResourceProvider.class)
+                .getBundleContext().getBundles();
+        for (Bundle bundle : bundles) {
+            if ("com.vaadin.flow.client".equals(bundle.getSymbolicName())) {
+                return bundle.getResource(path);
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public InputStream getClientResourceAsStream(String path)
+            throws IOException {
+        // No any caching !: flow-client may be reinstalled at any moment
+        return getClientResource(path).openStream();
+    }
+
+    private Class<?> getApplicationClass(Object context) {
+        Class<?> clazz = Objects.requireNonNull(context).getClass();
+        if (context instanceof VaadinServletService) {
+            clazz = ((VaadinServletService) context).getServlet().getClass();
+        }
+        if (!"com.vaadin.flow.server"
+                .equals(FrameworkUtil.getBundle(clazz).getSymbolicName())) {
+            return clazz;
+        }
+        return null;
+    }
+}